The invention provides a right-angled reflection type three-dimensional laser scanner and a method for realizing three-dimensional imaging by using the same. Coordinates of spatial points are acquired by using laser distance measurement and laser beam control data. Because the laser range is far, high depth of field can be acquired, and a shot object with large depth range can be scanned. For theshot object which can be born by a rotary table, the multi-side scanning can be realized, the multi-side surface textures of the shot object are acquired by shooting repeatedly through a camera, and a three-dimensional image of the shot object can be acquired through post treatment of the textures. For the object which cannot be born by the rotary table, multiple sides of the shot object can be shot by a plurality of times. Under the premise of ensuring larger scanning range, the whole device does not produce mechanical motion during working, the laser beam can be controlled only by two compact shafts, and the laser beam is not easily interfered by the outside; the 360-degree three-dimensional imaging of the outer lateral surface of the shot object is realized by adopting an auxiliary mode; and the three-dimensional imaging of a single lateral surface is realized by adopting an independent mode.